Fix incorrect comparison of frame size

The width and height stored in the reference frames are padded out to
a multiple of 16. The Width and Height variables in common are the
displayed size, which may be smaller. The incorrect comparison was
causing scaling related code to be called when it shouldn't have
been. A notable case where this happens is 1080p, since 1088 != 1080.

Change-Id: I55f743eeeeaefbf2e777e193bc9a77ff726e16b5